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Computational Thermodynamics in Materials Science Research Lab

Explore thermodynamic modeling, lattice stability, and phase evolution in materials science research. Investigate alloy design, interface reactions, and phase field simulations using computational methods. Collaborate with experts to advance scientific understanding.

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Computational Thermodynamics in Materials Science Research Lab

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  1. Byeong-Joo Lee Computational Materials Science & Engineering Lab.Pohang University of Science & Technology Computational Thermodynamics

  2. R&D in Materials Science and Engineering Structure Evolution Materials Property Process Condition Research Type I : experiments first, then thinking Research Type II: think first, then do experiments

  3. ThermodynamicModelling

  4. Lattice Stability

  5. Regular Solution vs. Quasi-Chemical Model

  6. Thermodynamic Assessment – Cr-Ni Binary System LfccCr,Ni = 8030 – 12.8801·T + (33080 – 16.0362·T)(1-2XNi) LbccCr,Ni = 17170 – 11.8199·T + (34418 – 11.8577·T)(1-2XNi) LliqCr,Ni = 318 – 7.3318·T + (16941 – 6.3696·T)(1-2XNi) B.-J. Lee, 1992

  7. Thermodynamic Assessment – Fe-Cr-Ni Ternary System B.-J. Lee 1993

  8. Thermodynamic Parameters (Fe,Cr,Mo)(Va,B,C,N)

  9. Thermodynamic Modeling – Gibbs Energy For a Phase with Formula Unit, (M1,M2,…,Mi,…)a(Va,C,N)c

  10. Thermodynamic Modeling – Gibbs Energy For a Phase with Formula Unit, (M1,M2,…,Mi,…)a(Va,C,N)c

  11. Thermodynamic Database for Steels –TCFe2000 → TCFe2 → TCFe3 Fe-Cr-Ni-Mo-Mn-Si-C-N +Nb-Ti-V-W-Al-Co-Cu-B-O-P-S 8C2 = 28 Binary Systems8C3 = 56 Ternary Systems19C2 = 171 Binary Systems19C3 = 969 Ternary Systems

  12. Solution Models - liquid and fcc Fe-C alloys

  13. Solution Model - liquid and fcc Fe-C alloys fcc : (Fe)1(Va,C) 1 Liquid : (Fe,C) Ternary (Fe,Mn)a(Va,C) c

  14. Applications ofComputational Thermodynamics

  15. Thermodynamic Calculation – Practical Steels

  16. Computational Thermodynamics의 적용 분야 Structural Materials (Steel, Solder, Al-, Ti-, Ni-, Mg-alloys), Semiconducting Materials, Ceramic Materials, Hydrogen Storage Materials, CVD process 등 열역학이 지배하는 모든 물질계 Thermodynamic Calculation – Application to Alloy Design

  17. Thermodynamic Calculation – Application to Alloy/Process Design AB1: 0.1C-5MN-7Al AB2: 0.2C-4Mn-6.6Al AB3: 0.3C-3.5Mn-6Al AB4: 0.4C-3.5Mn-5.8Al AB5: 0.5C-3Mn-4.9Al AB6: 0.3C-4Mn-7.3Al-0.05Ti

  18. Thermodynamics Assessment - Na-Al-H system

  19. Assessment of thermodynamic properties in the Li-Al-H ternary system

  20. Driving force of CVD Deposition ※ Example: Deposition of Silicon SiH4 + 2Cl2 = Si + 4HCl

  21. Interfacial Reactions

  22. Interfacial Reaction between Cu and Various Solder • Experimental Observation •    ▶ Cu/Sn : Cu6Sn5 •    ▶ Cu/Sn-Pb eutectic : Cu6Sn5 •    ▶ Cu/Sn-Ag eutectic : Cu6Sn5 •    ▶ Cu/Sn-Zn eutectic : CuZn_γ •    ▶ Cu/Sn-In eutectic : Cu2(Sn,In) or Cu2In3Sn

  23. Application to Solder/Substrate Interfacial Reactions – Cu/Sn Reaction

  24. Application to Solder/Substrate Interfacial Reactions – Cu/Sn Reaction

  25. Application to Thin Film Reactions – Metal/Si Reaction

  26. Application to Thin Film Reactions – Metal/Si Reaction

  27. Application to Thin Film Reactions – Metal/Si Reaction

  28. Application to Thin Film Reactions – Metal/Si Reaction

  29. Application to Interfacial Reactions – Metal/Si Reaction

  30. Computational Materials Science & Engineering Lab.Pohang University of Science & Technology, Korea Thermodynamics Nano Materials Eunha Kim Inyoung Sa Byeong-Moon Lee and Byeong-Joo Lee

  31. Curvature Effect– Capillary Pressure System condition T = constant Vα = Vβ = V = constant @ equilibrium

  32. Curvature Effect– Capillary Pressure Effect on Melting Point of Nano Particle

  33. Melting points of Gold Nano Particles: B-J Lee, 2009

  34. Melting points of Nano Particles: B-J Lee, 2009 Pt Ni Au W Mg Pt

  35. Melting points of Nano Wires: B-J Lee, 2009 Ni Pt Au W Mg Pt

  36. Motivation- in Collaboration with M.-H. Jo, POSTECH

  37. Vapor-Liquid Liquid-Solid SiH4 + GeH4 + H2 ① ② Reactions during the VLS Process

  38. Vapor-Liquid Liquid-Solid SiH4 + GeH4 + H2 ① ① ② ② Reactions during the VLS Process 200 torr 400 oC

  39. VLS Growth of Nanowires - GeSi Nanowires

  40. Size dependence of SiGe nanowire composition

  41. Size dependence of SiGe nanowire composition CALPHAD (2008)

  42. Interfacial Phenomena – Segregation (Guttmann, Butler/Tanaka) Assume a one atomic layer surface phase and consider equilibrium between bulk and surface where ωi is the molar surface area Assume ωi = ωj = … = ω

  43. Calculation of Surface Tension of Liquid Alloys

  44. Calculation of Surface Segregation in Solid Alloys

  45. Computational Thermodynamics as Materials Genome Computational Thermodynamics + First-Principles Calculation

  46. Application to Metal/Ceramics Interfacial Reactions – Ti/Al2O3 Reaction

  47. Application to Metal/Ceramics Interfacial Reactions – Ti/Al2O3 Reaction

  48. Phase Field Simulation of γ→α transformation in steels Wetting angle : 36o Wetting angle : 120o Fe - 0.5% Mn – 0.1% C, dT/dt = 1 oC/s from SG Kim, Kunsan University

  49. Summary Computational Thermodynamics • Calculation of Multi-component Phase Diagrams • Interfacial Reactions • – Metal/Liquid Solder, Metal/Ceramics • Thin Films Reactions • – Metal/Silicon • Thermodynamics of Nano Materials • – Capillarity Effect

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